題目列表(包括答案和解析)
A black hole is created when a large star burns out. Like our sun, stars are unbelievably hot furnaces (熔爐) that burn their own matter as fuel. When most of the fuel is used up, the star begins to die.
The death of a star is not a quiet event. First there is a huge explosion. As its outer layer is blasted off into space, the dying star shines as brightly as a billion suns.
After the explosion gravity pulls in what’s left of the star. As the outside of the star sinks toward the center, the star gets smaller and smaller. The material the star is made of becomes tightly packed together. A star is so dense that a teaspoon of matter from it weighs billion of pounds.
The more the star shrinks, the stronger the gravity inside it becomes. Soon the star is very tiny, and the gravity pulling it in is unbelievably strong. In fact, the gravity is so strong that it even pulls light into the star! Since all the light is pulled in, none can go out. The star becomes black when there is no light. Then a black hole is born!
That’s what we know about black holes. What we don’t know is this: What happens inside a black hole after the star has been squeezed into a tiny ball? Does it keep getting smaller and smaller forever? Such a possibility is hard to imagine.
But if the black hole doesn’t keep shrinking, what happens to it? Some scientists think black holes are like doorways to another world. They say that as the star disappears from our universe, it goes into another universe. In other words a black hole in our universe could turn into a “white hole” in a different universe. As the black hole swallows light, the white hole shines brightly—somewhere else. But where? A different place, perhaps, or a different time — many years in the past or future.
Could you travel through a black hole? Right now, no. Nothing we know of could go into a black hole without being crushed. So far the time being, black hole must remain a mystery.
Black holes are a mystery—but that hasn’t stopped scientists from dreaming about them. One scientist suggested that in the future we might make use of the power of black holes. They would supply all of Earth’s energy needs, with plenty to spare. Another scientist wondered if a black hole could some day be used to swallow earthly waste—a sort of huge waste disposal(處理) in the sky!
When the star begins to die ______.
A. there is no fuel left in it B. its outer layer goes into space first
C. a huge explosion will happen D. it doesn’t give off light any longer
Which of the following doesn’t help produce a black hole?
A. The gravity inside the star is very strong. B. The light can’t go out of the star.
C. The star becomes smaller and smaller D. The dying star shines very brightly.
The black hole ______.
A. continues becoming smaller and smaller all the time
B. goes into another universe and becomes a white hole
C. can pull in everything we know of in the world
D. will appear at another place at a different time
What’s the best title for this passage?
A. A New Scientific Discovery: Black Holes
B. How Do Black Holes Come Into Being?
C. What Are Black Holes?
D. Travel Through A Black Hole
C
By far the most common difficulty in studying is simple failure to get down to regular concentrated work. This difficulty is much greater for those who do not work to a plan and have no regular routine of study. Many students muddle (胡亂對付) along, doing a bit of this subject or that, as the mood takes them, or letting their set work pile up until the last possible moment.
Few students work to a set timetable. They say that if they did work out a timetable for themselves they would not keep to it, or would have to change it frequently, since they can never predict from one day to the next what their activities will be.
No doubt some students are more willing to accept a regular routine than others. There are many who shy away from a self-controlled weekly timetable, and dislike being tied down to a fixed program of work. Many able students state that they work in cycles. When they become interested in a topic, they work on it attentively for three or four days at a time. On other days they avoid work completely. It has to be admitted that we do not fully understand the motivation (動機)to work.. Most people over 25 years of age have become used to routine, and the majority of real productive workers set aside regular hours for the more important areas of their work. The “tough-minded” school doesn’t fully accept the idea that good work can only be done naturally, under the influence of inspiration.
Those who believe that they need only work and study as the fit takes them have a mistaken belief either in their own talent or in the value of “freedom”. In fact, freedom from control and discipline（紀律）leads to unhappiness rather than to “self-expression” or “personality development”. Our society insists on regular habits, timekeeping and punctuality (準時), and whether we like it or not, if we mean to make our way in society, we have to meet its demands.
The most widespread problem in applying oneself to study is ______.
A．changing from one subject to another
B．the failure to keep to a set timetable of work
C．the unwillingness to follow a systematic plan
D．working on a subject only when one feels like it
Which of the following is true?
A．Many students are not interested in using self-controlled timetable.
B．Many students don’t like being told to study to a fixed timetable.
C．Most people of over 25 years of age don’t work to a set timetable.
D．Tough-minded people agree that good job is done naturally
The underlined part “as the fit takes them” in paragraph 4 probably means ______.
A．when they have the energy
B．when they are in the mood
C．when they feel fit
D．when they find conditions are suitable
A suitable title for the passage might be ______.
A．Attitudes to Study B．A study Plan
C．The Difficulties in Studying D．Study and Self-discipline
A black hole is created when a large star burns out. Like our sun, stars are unbelievably hot furnaces(熔爐) that burn their own matter as fuel. When most of the fuel is used up, the star begins to die.
The death of a star is not a quiet event. First there is a huge explosion. As its outer layer is blasted off into space, the dying star shines as brightly as a billion suns.
After the explosion gravity pulls in what’s left of the star. As the outside of the star sinks toward the center, the star gets smaller and smaller. The material the star is made of becomes tightly packed together. A star is so dense that a teaspoon of matter from it weighs billion of pounds.
The more the star shrinks, the stronger the gravity inside it becomes. Soon the star is very tiny, and the gravity pulling it in is unbelievably strong. In fact, the gravity is so strong that it even pulls light into the star! Since all the light is pulled in, none can go out. The star becomes black when there is no light. Then a black hole is born!
That’s what we know about black holes. What we don’t know is this: What happens inside a black hole after the star has been squeezed into a tiny ball? Does it keep getting smaller and smaller forever? Such a possibility is hard to imagine.
But if the black hole doesn’t keep shrinking, what happens to it? Some scientists think black holes are like doorways to another world．They say that as the star disappears from our universe, it goes into another universe. In other words a black hole in our universe could turn into a “white hole” in a different universe. As the black hole swallows light, the white hole shines brightly — somewhere else. But where? A different place, perhaps, or a different time — many years in the past or future.
Could you travel through a black hole? Right now, no. Nothing we know of could go into a black hole without being crushed．So far the time being, black hole must remain a mystery.
Black holes are a mystery—but that hasn’t stopped scientists from dreaming about them. One scientist suggested that in the future we might make use of the power of black holes. They would supply all of Earth’s energy needs, with plenty to spare. Another scientist wondered if a black hole could some day be used to swallow earthly waste—a sort of huge waste disposal (處理) in the sky!
When the star begins to die ______.
A．there is no fuel left in it B．its outer layer goes into space first
C．a huge explosion will happen D．it doesn’t give off light any longer
Which of the following doesn’t help produce a black hole?
A．The gravity inside the star is very strong.
B．The light can’t go out of the star.
C．The star becomes smaller and smaller
D．The dying star shines very brightly.
The black hole ______.
A．continues becoming smaller and smaller all the time
B．goes into another universe and becomes a white hole
C．can pull in everything we know of in the world
D．will appear at another place at a different time
What’s the best title for this passage?
A．A New Scientific Discovery: Black Holes
B．How Do Black Holes Come Into Being?
C．What Are Black Holes?
D．Travel Through A Black Hole
D
Life has changed in Mexico City．Streets normally filled with people are empty．One of the most popular professional soccer teams recently played a game in an empty stadium that can seat more than100,000 people．It's swine （豬）flu that has made life in Mexico City grind to a halt （慢慢停了下來）．
Seemingly out of nowhere, swine flu has caused confirmed deaths in 12 countries as of April 30．It has sent a wave of alarm around the world．Governments are trying to find ways to prevent further out-breaks．The World Health Organization has raised its swine flu global threat level to five out of six．
People may be familiar with bird flu, but they know little about swine flu．Swine flu is a contagious（傳染性） respiratory（呼吸的）disease in pigs．It is caused by a type-A influenza virus．
Humans can also catch swine flu．The virus causes regular outbreaks in pigs, but people usually do not catch it．However, there have been cases of the virus spreading to people, and then from one person to another．
The symptoms of swine flu are similar to the common flu．They include fever, lethargy （無精打采）, lack of appetite, coughing, runny nose, sore throat, nausea（惡心）, and vomiting （嘔吐）．The high proportion of young adults among the deaths is one of several mysteries about this virus．Most of the dead had lung damage．What caused it is not yet known．
The virus spreads the same way the common flu does．When an infected person coughs or sneezes around another person, the latter is put at risk．People can get the disease by touching something with the flu virus on it and then touching their mouth, nose or eyes．
There are medicines to treat swine flu．Doctors suggest using anti - viral drugs．They keep the virus from reproducing inside the body．
And there are vaccines for it now, several everyday steps can also help prevent the spread of the virus: washing hands frequently; avoiding close contact with people who are sick; and avoiding touching surfaces that might have the virus on it．
People may worry that they will get swine flu from eating or preparing pork．In fact, you cannot catch the virus from pork products if they have been properly prepared and cooked．Cooking food at temperatures of 71℃ kills the virus．
69．What is the main idea of the passage?
A．It mainly tells us how swine flu broke out in Mexico City．
B．It presents the reader with some information concerning swine flu．
C．It tells us the differences between swine flu and bird flu．
D．It mainly tells readers the dangers caused by swine flu．
70．The following tips can protect us from swine flu EXCEPT _________．
A．keeping us away from other people
B．washing hands frequently
C．avoiding close contact with sick people
D．avoiding touching surfaces that might have the virus on them
71．What's the main idea of the first paragraph?
A．Mexico City is really a place of horror now．
B．People in Mexico City like staying at home．
C．People in Mexico City don't like soccer．
D．Swine flu has seriously affected people's life in Mexico City．
72．What can we infer from the passage?
A．At present there still aren't effective vaccines for swine flu．
B．Swine flu is preventable，controllable and curable．
C．From now on, people can't eat pork if they want to be safe．
D．All of the dead killed by swine flu had lung damage．
A black hole is created when a large star burns out. Like our sun, stars are unbelievably hot furnaces (熔爐) that burn their own matter as fuel. When most of the fuel is used up, the star begins to die.
The death of a star is not a quiet event. First there is a huge explosion. As its outer layer is blasted off into space, the dying star shines as brightly as a billion suns.
After the explosion gravity pulls in what’s left of the star. As the outside of the star sinks toward the center, the star gets smaller and smaller. The material the star is made of becomes tightly packed together. A star is so dense that a teaspoon of matter from it weighs billion of pounds.
The more the star shrinks, the stronger the gravity inside it becomes. Soon the star is very tiny, and the gravity pulling it in is unbelievably strong. In fact, the gravity is so strong that it even pulls light into the star! Since all the light is pulled in, none can go out. The star becomes black when there is no light. Then a black hole is born!
That’s what we know about black holes. What we don’t know is this: What happens inside a black hole after the star has been squeezed into a tiny ball? Does it keep getting smaller and smaller forever? Such a possibility is hard to imagine.
But if the black hole doesn’t keep shrinking, what happens to it? Some scientists think black holes are like doorways to another world. They say that as the star disappears from our universe, it goes into another universe. In other words a black hole in our universe could turn into a “white hole” in a different universe. As the black hole swallows light, the white hole shines brightly—somewhere else. But where? A different place, perhaps, or a different time — many years in the past or future.
Could you travel through a black hole? Right now, no. Nothing we know of could go into a black hole without being crushed. So far the time being, black hole must remain a mystery.
Black holes are a mystery—but that hasn’t stopped scientists from dreaming about them. One scientist suggested that in the future we might make use of the power of black holes. They would supply all of Earth’s energy needs, with plenty to spare. Another scientist wondered if a black hole could some day be used to swallow earthly waste—a sort of huge waste disposal(處理) in the sky!
When the star begins to die ______.
A. there is no fuel left in it B. its outer layer goes into space first
C. a huge explosion will happen D. it doesn’t give off light any longer
Which of the following doesn’t help produce a black hole?
A. The gravity inside the star is very strong. B. The light can’t go out of the star.
C. The star becomes smaller and smaller D. The dying star shines very brightly.
The black hole ______.
A. continues becoming smaller and smaller all the time
B. goes into another universe and becomes a white hole
C. can pull in everything we know of in the world
D. will appear at another place at a different time
What’s the best title for this passage?
A. A New Scientific Discovery: Black Holes
B. How Do Black Holes Come Into Being?
C. What Are Black Holes?
D. Travel Through A Black Hole
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